A previous study pointed out that strong response to immunotherapy in non-small-cell lung cancer patients is related to high APOBEC signatures,25 and another reported high PD-1 expression in hypermutated bladder cancer tumours with APOBEC signatures.33 Therefore, the high immunogenicity of the IR type may be related to the high APOBEC activity in the tumour cells. This evidence concerns the gene PDCD1 and urinary bladder carcinoma.